This disclosure relates to a mount assembly or damper, and particularly a mount assembly that damps vibrations imposed on the assembly in a load bearing environment, including a fluid effect damping that is a combination of frequency dependent resonant damping and broadband viscous damping.
Assemblies that damp vibrations and relative movement between components are well known. Many of these arrangements use an elastomer or natural rubber material disposed between first and housing portions that are secured to first and second vehicle components. It is desirable to limit vibration from the first component to the second component, for example, between a first component such as an automotive frame and a second component such as an engine. For example, an engine mount assembly includes a first housing portion mounted to the frame and a second housing portion secured to the engine and a material such as an elastomer or rubber interposed between the first and second housing portions that damps the vibrations.
When a component in a system is excited at its natural frequency, it can begin vibrating at high amplitudes. These high amplitude vibrations can be transferred from the origin of the excitation through a conventional mount to the side of the system where vibrations are not desirable. An axially damped hydraulic mount can be tuned to the natural frequency of the system and can reduce the transfer of vibrations from one side of the system to the other.
Other axially damped hydraulic mounts are known in the art. Moreover, it is also known to use a true double pumping hydraulic mount in which a hydraulic fluid is selectively conveyed between first (upper) and second (lower) chambers that are interconnected by an elongated path (inertia track). However, these types of hydraulic mounts have some functional limitations because of the need to secure the hydraulic mount via the housing to the surrounding environment.
It is also desirable to use the mount as a load bearing mount, or in combination with a typical shear style body mount in a rebound application, or an engine mount, or suspension mount application. Further, if used in such a combination, undue complexity in the assembly and sealing should also be avoided.